A flame-retardant fabric includes 20% by mass or more and less than 40% by mass of silica-containing cellulose fibers, 25 to 55% by mass of flame-retardant cellulose fibers containing a phosphorus-based flame retardant, and 10 to 50% by mass of aramid fibers. The flame-retardant fabric is easy to dye and exhibits high flame retardancy in flammability tests. A work clothing contains the flame-retardant fabric.